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        <p>|| — 
      Logical OR operator.
          </p>
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      <div class="refsect1">
        <a id="idp88661888"></a>
        <h2>Description</h2>
        <p>
      Arithmetic operators perform operations of change-sign (negate), don't-change-sign, logical AND logical OR, add, subtract, multiply and divide. Note that a value or an expression may fall between two of these operators, either of which could take it as its left or right argument, as in
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a + b * c.<br />
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        <p>
      In such cases three rules apply:
    </p>
        <p>
      1. * and <span class="emphasis"><em>/</em></span> bind to their neighbors more strongly than + and −. Thus the above expression is taken as
      </p>
        <div class="literallayout">
          <p>  <br />
a + (b * c)<br />
      </p>
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        <p>
      with * taking b and c and then + taking a and b * c.
    </p>
        <p>
      2. <span class="emphasis"><em>+</em></span> and <span class="emphasis"><em>−</em></span> bind more strongly than &amp;&amp;, which in turn is stronger than ||:
      </p>
        <div class="literallayout">
          <p>  <br />
a &amp;&amp; b - c || d<br />
      </p>
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        <p>
      is taken as
      </p>
        <div class="literallayout">
          <p>  <br />
(a &amp;&amp; (b - c)) || d<br />
      </p>
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        <p>
    </p>
        <p>
      3. When both operators bind equally strongly, the operations are done left to right:
      </p>
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          <p>  <br />
a - b - c<br />
      </p>
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        <p>
      is taken as
      </p>
        <div class="literallayout">
          <p>  <br />
(a - b) - c<br />
      </p>
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        <p>
    </p>
        <p>
      Parentheses may be used as above to force particular groupings.
    </p>
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      <div class="refsect1">
        <a id="idp88672992"></a>
        <h2>Syntax</h2>
        <pre class="synopsis">a <span class="command"><strong>||</strong></span> b  (logical OR; not audio-rate)</pre>
        <p>
      where the arguments <span class="emphasis"><em>a</em></span> and <span class="emphasis"><em>b</em></span> may be further expressions.
    </p>
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      <div class="refsect1">
        <a id="idp88676464"></a>
        <h2>Examples</h2>
        <p>
      Here is an example of the | operator. It uses the file <a class="ulink" href="examples/logicOR.csd" target="_top"><em class="citetitle">logicOR.csd</em></a>.
      </p>
        <div class="example">
          <a id="idp88678288"></a>
          <p class="title">
            <strong>Example 34. Example of the | operator.</strong>
          </p>
          <div class="example-contents">
            <p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p>
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>
<span class="comment">; Select audio/midi flags here according to platform</span>
-odac -+rtmidi=virtual -M0   <span class="comment">;;;realtime audio out and virtual midi keyboard</span>
<span class="comment">;-iadc    ;;;uncomment -iadc if realtime audio input is needed too</span>
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>
<span class="comment">;after a UDO from Rory Walsh</span>
<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">ksmps</span> <span class="op">=</span> 32
<span class="ohdr">nchnls</span> <span class="op">=</span> 2

<span class="oblock">instr</span> 1	<span class="comment">;displays notes, midi channel and control number information</span>

kstatus, kchan, kdata1, kdata2 <span class="opc">midiin</span>
k1 <span class="opc">changed</span> kstatus
k2 <span class="opc">changed</span> kchan
k3 <span class="opc">changed</span> kdata1
k4 <span class="opc">changed</span> kdata2
<span class="octrl">if</span>((k1<span class="op">==</span>1)<span class="op">||</span>(k2<span class="op">==</span>1)<span class="op">||</span>(k3<span class="op">==</span>1)<span class="op">||</span>(k4<span class="op">==</span>1)) then
<span class="opc">printks</span> "Value<span class="op">:</span><span class="op">%</span>d ChanNo<span class="op">:</span><span class="op">%</span>d CtrlNo<span class="op">:</span><span class="op">%</span>d\n" , 0, kdata2, kchan, kdata1  
<span class="octrl">endif</span> 

<span class="oblock">endin</span>
<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>

<span class="stamnt">i</span>1  0  60	<span class="comment">;print values for 60 seconds</span>

<span class="stamnt">e</span>
<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
          </div>
        </div>
        <p><br class="example-break" />

      Its output should include a line like these:
      </p>
        <pre class="screen">
Value:127 ChanNo:11 CtrlNo:62
Value:127 ChanNo:11 CtrlNo:60
Value:127 ChanNo:11 CtrlNo:60
Value:127 ChanNo:11 CtrlNo:60
Value:127 ChanNo:11 CtrlNo:60
....
Value:0 ChanNo:11 CtrlNo:62
Value:0 ChanNo:11 CtrlNo:62
Value:0 ChanNo:11 CtrlNo:62
Value:0 ChanNo:11 CtrlNo:62
....
Value:77 ChanNo:11 CtrlNo:23
Value:77 ChanNo:11 CtrlNo:23
Value:76 ChanNo:11 CtrlNo:23
Value:76 ChanNo:11 CtrlNo:23
....</pre>
        <p>
    </p>
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      <div class="refsect1">
        <a id="idp88683648"></a>
        <h2>See Also</h2>
        <p>
      <a class="link" href="subtracts.html" title="-"><em class="citetitle">-</em></a>, 
      <a class="link" href="adds.html" title="+"><em class="citetitle">+</em></a>, 
      <a class="link" href="opand.html" title="&amp;&amp;"><em class="citetitle">&amp;&amp;</em></a>, 
      <a class="link" href="multiplies.html" title="*"><em class="citetitle">*</em></a>, 
      <a class="link" href="divides.html" title="/"><em class="citetitle">/</em></a>, 
      <a class="link" href="raises.html" title="^"><em class="citetitle">^</em></a>, 
      <a class="link" href="modulus.html" title="%"><em class="citetitle">%</em></a>
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